Amana MVC80 Installation Instructions Manual page 35

t
roubleShooting
Symptom
Induced draft blower and
circulator blower runs
continuously
No furnace operation
No furnace operation
Normal furnace operation
Furnace fails to operate
Furnace fails to operate on
high stage; furnace operates
normally on low stage
Induced draft blower
operating
Furnace fails to operate on
high stage; furnace operates
normally on low stage
Induced draft blower
operating
Furnace fails to operate
Furnace fails to operate
Furnace fails to operate
C
hart
LED Status Fault Description
Flame sensed with no call for
heat
Short to ground in flame sense

circuit
Lingering burner flame
Slow closing gas valve
Open fuse

Short in low voltage wiring
Flame sense micro amp signal is
low
Flame sensor is coated/oxidized

Flame sensor incorrectly
positioned in burner fame
Lazy burner flame due to
improper gas pressure or
combustion air
Problem with igniter circuit
Improperly connected or shorted
igniter

Poor unit ground
Igniter relay fault on integrated
control module
High stage pressure switch
circuit is closed at start of
heating cycle.

High stage pressure switch
contacts sticking
Shorts in pressure switch circuit
wiring
High stage pressure switch
circuit is not closed

Furnace is operating on low
stage only
Polarity of 115 volt AC is
reversed

Poor unit ground
Gas valve is not energized when
it should be

External Gas Valve Error
Gas valve is energized when it
should not be

Internal gas valve error
Correct short at flame sensor or in flame sensor
wiring
Check for lingering or lazy flame
Verify proper operation of gas valve
Replace fuse
Locate and correct short in low voltage wiring
Clean flame sensor if coated or oxidized
Inspect for proper flame sensor alignment
Check inlet air piping for blockage, proper length,
elbows, and termination
Compare current gas pressure to rating plate and
adjust as needed
Check and correct wiring from integrated control
module to igniter
Diagnose and replace shorted igniter as needed
Verify and correct unit ground wiring if needed
Check igniter output from control, replace if
necessary
Diagnose and replace high stage pressure switch if
needed
Repair short in wiring
Inspect pressure switch hose, repair/replace if
necessary
Inspect flue and/or inlet air piping for blockage,
proper length, elbows, and termination
Check drain system, correct as necessary
Check induced draft blower performance, correct
as necessary
Tighten or correct wiring connection
Correct polarity, check and correct wiring if
necessary
Verify proper ground, correct if necessary
Check wiring in gas valve circuit
Replace integrated control board
Check wiring in gas valve circuit
Replace integrated control board
35
Corrective Actions